The present invention relates generally to methods and systems for suppressing interference in a mobile communication system and, more particularly, to methods and systems for suppressing intercell interference.
Orthogonal Frequency Division Multiplexing (OFDM) and Code Division Multiple Access (CDMA) systems are limited by interference. The interference may generally be categorized as intracell interference and intercell interference. Intracell interference is interference attributable to interfering sources (e.g., other users) in the same cell or sector and intercell interference is interference attributable to interfering sources in a neighboring cell or sector. Multi-user detection techniques have been developed to reduce or suppress intracell interference attributable to interfering sources in the same cell. In the case of intercell interference, suppression of the interference is more difficult because knowledge of the interfering signals is generally not available. Thus, the intercell interference is typically suppressed using statistical parameters related to the interference. These statistical parameters may be difficult to estimate over a short period of time. Further, interference suppression based on the use of statistical information is typically less effective than suppression of interference based on knowledge of the interfering signals. Therefore, there is an interest in developing methods and systems for reducing intercell interference beyond what is typically achieved using statistical parameters of the interference.